These are RGB LEDs with their own microcontroller, so all LEDs can be programmed individually. They are daisy chained, first the two in the lower area of the PCB and then six on the antenna on the top. So if you don't want to add all LEDs, or want to start with only one first, you have to follow the order “middle left, middle right, antenna from right to left” or bridge the data pins of the unused LED pads.

Important note Due to a fn0rd in the layout the transistors intended to control power of the LEDs can't be used as intended. The transistor pads have not been populated. There are several ways of getting the LEDs to work:

build some complex SMD sculpture using wires (more about this at the bottom of the page)

build a working high-side switch using two MOSFETs to get the functionality that was originally intended (or optionally to switch LED power with a GPIO port)

try to use a jumper/switch to bridge two of the transistor pads

bridge two of the transistor pads with solder

The last option has the disadvantage that the blue LED will be a bit dimmer but it is the easiest option and the LEDs are quite bright already.

There are spaces for capacitors which are recommended, but the LEDs usually work fine without.

Which way around do the LEDs go?

If you have a close look at an LED, you'll notice one corner is marked by having a bit cut off. In the photo below, the pads where this corner needs to be are marked in red:

How to supply the LEDs with power

Do not bridge all three pads of each transistor as this will create a short!

Example with all possible LEDs and correct bridges on two of the three transistor pins (for power supply) soldered (LEDs green, bridges red):

I soldered one LED but it doesn't work?

All LEDs are on the same data line, if they are not all soldered on, the data line is interrupted. You can either solder on all LEDs or bridge the data line. The image below shows where the data line goes, red lines are on the PCB, green lines are usually closed by LEDs. If you are not filling all LED spots, you have to fill the missing connections with wire.

Will the LEDs do something as soon as I switch the rad1o on?

no.

Switch off your badge, press the joystick to the left (in the direction of DARC). Select TESTAPP, and then ws2812b.

How should the test pattern look like?

The 2 lower LEDs should be yellow, the one at the tip of the antenna should be green and the other 5 LEDs on the antenna blue.